The experiments are broadly designed to study changes in vessels and organs in a variety of disorders. They include detailed studies of the effects of tolerance to catecholamines on endotoxin shock, anaphylaxis, and the Shwartzman phenomenon; conventional and ultrastructural study of animals at varied intervals following implantation of an artificial heart, and detailed studies on the effects of various stimuli on the phagocytic functions of alveolar macrophages.